• The Korean Journal of Applied Statistics
• /
• v.37 no.4
• /
• pp.455 -465
• /
• 2024

SMOTE (synthetic minority over-sampling technique) has been used the most as a solution to the problem of imbalanced data. SMOTE selects the nearest neighbor based on Euclidean distance. However, Euclidean distance has the disadvantage of not considering the correlation between variables. In particular, the Mahalanobis distance has the advantage of considering the covariance of variables. But if there are outliers, they usually influence calculating the Mahalanobis distance. To solve this problem, we use the Mahalanobis distance by estimating the covariance matrix using MCD (minimum covariance determinant). Then apply Mahalanobis distance based on MCD to SMOTE to create new data. Therefore, we showed that in most cases this method provided high performance indicators for classifying imbalanced data.

• Journal of Institute of Control, Robotics and Systems
• /
• v.17 no.2
• /
• pp.149-156
• /
• 2011

This paper reveals a distance estimation algorithm based on multi-code ultrasonic and wireless sensor network. For measuring the distances among the sensor nodes, each ultrasonic transmitter transmits multi-code ultrasonic signal simultaneously. Receivers use cross correlation method to separate the coded signals. The information of measured distances is broadcasted to each sensor node by wireless sensor network. The wireless sensor network measures the distance among the sensor nodes using the received signal strength of the broadcasting. The multi-code ultrasonic have a limitation of measurable distance. And the received signal strength is affected from an environment. This paper measures a distance using ultrasonic and a received signal strength in short range. These measured data are applied to the least square estimation algorithm. By the expansion of the fitting curve, a distance measurement in long range using the received signal strength is compensated. The coupled system reduce the error to an acceptable level.

• Korean Journal of Acupuncture
• /
• v.33 no.1
• /
• pp.18-32
• /
• 2016

Objectives : This study aims to analyze the co-occurrence of pathological symptoms and corresponding acupoints as documented by the comprehensive acupuncture and moxibustion records in the classical texts of Far East traditional medicine as an aid to a more efficient understanding of the tacit treatment principles of ancient physicians. Methods : The Classic of Nourishing Life with Acupuncture and Moxibustion(Zhenjiu Zisheng Jing; hereinafter ZZJ) was selected as the primary reference book for the analysis. The pathology-acupoint co-occurrence analysis was performed by applying 4 values of vector space measures(weighted Euclidean distance, Euclidean distance, $Cram\acute{e}r^{\prime}s$ V and Canberra distance), which measure the distance between the observed and expected co-occurrence counts, and 3 values of probabilistic measures(association strength, Fisher's exact test and Jaccard similarity), which measure the probability of observed co-occurrences. Results : The treatment records contained in ZZJ were preprocessed, which yielded 4162 pathology-acupoint sets. Co-occurrence was performed applying 7 different analysis variables, followed by a prediction simulation. The prediction simulation results revealed the Weighted Euclidean distance had the highest prediction rate with 24.32%, followed by Canberra distance(23.14%) and association strength(21.29%). Conclusions : The weighted Euclidean distance among the vector space measures and the association strength among the probabilistic measures were verified to be the most efficient analysis methods in analyzing the correlation between acupoints and pathologies found in the classical medical texts.

• Journal of Periodontal and Implant Science
• /
• v.34 no.3
• /
• pp.535-541
• /
• 2004

The aims of the present study are firstly to investigate the amount of bone loss around non-submerged implants placed in the posterior region and secondly to investigate the relationship between inter-implant and implant-tooth distance and peri-implant bone loss. Thirty-one subjects with 60 implants were selected consecutively from the implant patient pool at the department of Chonbuk National University Hospital. To be included in the study subject, the implant should have been functioned more than 6 months after loading. Inter-implant and implant-tooth distance, distance between implant shoulder and the first bone contact with the implant(DIB) were measured from the scanning image of the radiograph of each implant. The result showed that; 1. inter-implant distance has a statistically significant relationship with DIB in Pearson correlation analysis. 2. the DIB at the implant facing surface of the implant was greater than that of tooth facing surface of the implant. Within limitation of this study, it is suggested to place an implant not too closely to adjacent implants, and the presence of a tooth adjacent to an implant may keep the level of tooth-facing surface of the implant. Further studies with a prospective design are needed to elucidate the relationship between bone changes and various dimensions around implants.

• The Korean Journal of Pain
• /
• v.9 no.2
• /
• pp.349-353
• /
• 1996

Background: Although the paramedian approach for epidural blockade is useful in some clinical situation, the parameters which are correlated with the distance from skin to the epidural space has not been established. Methods: We studied in 143 patients having elective continuous epidural blocks for relief of postoperative pain. All blocks were performed using paramedian approach with Tuohy needle in the lumbar (group 1, n=100) and thoracic (group 2, n=45) area. We measured the distance from skin to the epidural space, body weight, height, and the angle between the shaft of the needle and the skin. Data were analyzed by linear regression. The relationships between parameters identified by the F-test with a P value of less than 0.05 were considered statistically significant. Results: The mean distance from skin to the lumbar epidural space was $4.4{\pm}0.7$ cm. significant correlation between the body weight and the depth of lumbar epidural space ($\gamma$ value : 0.492) was noted with regression equation of depth(cm)=2.293+0.034${\times}$body weight (kg). Also the significant correlation between the ponderal index (PI) and the depth of lumbar epidural space ($\gamma$ value : 0.539) was noted with regression equation of depth(cm)=1.703+0.07${\times}$PI, The mean distance from skin to the thoracic epidural space was $5.2{\pm}0.7cm$ which did not correlated with other anatomic measurements. Conclusion: We found that PI and body weight are the suitable predictors of the depth of the lumbar epidural space, but not the thoracic epidural space.

• Korean Journal of Biological Psychiatry
• /
• v.22 no.1
• /
• pp.14-19
• /
• 2015

Objectives The purpose of this study is to find the cephalometric variables which are significantly correlated with the apnea-hypopnea index (AHI) in suspected Korean obstructive sleep apnea (OSA) patients. Methods We examined lateral cephalogram and attended-full night laboratory polysomnography of the 40 participants who complained of OSA symptoms. The correlation analysis was conducted to find the cephalometric variables which are significantly correlated with the AHI. Results The correlation analysis showed that the higher AHI was associated with the longer distance between hyoid and mandibular plane (p = 0.023), the longer distance between C3 and hyoid (p = 0.014), the longer tongue length (p = 0.003), the larger inferior tongue area (p = 0.008), the larger anterior displacement of the hyoid bone (p = 0.024), the longer distance between posterior nasal spine and the tip of the soft palate (p = 0.021), and the larger cross-sectional area of soft palate (p = 0.001) of cephalogram in erect position. The higher AHI was correlated with the longer distance between hyoid and mandibular plane (p = 0.008), the longer tongue length (p = 0.037), the larger inferior tongue area (p = 0.013), the thicker uvula (p = 0.004), the longer distance between retrognathion and hyoid (p = 0.025), and larger cross-sectional area of soft palate (p = 0.001) of cephalogram in supine position. Conclusions The present preliminary results showed the candidate measurements of cephalogram which are significantly correlated with the AHI in suspected OSA.

• Physical Therapy Korea
• /
• v.17 no.2
• /
• pp.25-32
• /
• 2010

The purpose of this study was to investigate the most effective and comprehensible method for the assessment of resting scapular position (RSP) and pain level (PL) in unilateral shoulder pain (USP). Fifty volunteers with USP were involved in the study. Resting scapular assessments of the patients' pain sides (PS) and non-pain sides (NPS) were evaluated. The assessment tools for RSP are: 1) sternal notch (SN) to coracoid process (CP) distance 2) 3rd thoracic spinous process (T3S) to posterolateral angle of acromion (PLA) distance 3) scapular index 4) 8th thoracic spinous process (T8S) to inferior angle of scapular (IAS) distance 5) supine measurement of pectoralis minor (PM) distance 6) standing PM distance 7) PM index (PMI) and 8) PM pain. The paired t-test was used to compare PS and NPS in RSP. Pearson correlation analysis was used to confer a relationship between the PL and RSP. The results of this study indicated that: 1) all the variables between the PS and NPS for RSP were statistically significant(p<.05) and 2) the PMI showed the strongest relationship in the correlation analysis between RSP and PL(p<.05, r=.37). Therefore, it can be concluded that there is a relationship between PMI and PL and it is suggested that an assessment tool using PMI to diagnose shoulder pain would be clinically effective.

• Explosives and Blasting
• /
• v.29 no.2
• /
• pp.43-50
• /
• 2011

This study measured a vibration level at each distance of construction fields where blasts occur using Lion measuring instrument and used BlastmateIII to measure vibration velocity at the same distance. A total 130 blasts occurred with the weight of a total of 5,180 kg and the number of blast holes per blast was 5, 10 and 20. The weight of 4 kg was used for each hole. Vibrations caused by blast was measured at the distance with the same velocity and level. Measurements were carried 15~102 m away from the blast source. and 273 data on vibration velocity and level were obtained from eight measurements. It analysed data on vibration velocity measured based on existing correlation formulas and compared them to real measurements to analyse interrelationship.

• Archives of Plastic Surgery
• /
• v.33 no.4
• /
• pp.469-473
• /
• 2006

Purpose: The transverse rectus abdominis myocutaneous(TRAM) flap has become a reliable method for autogenous breast reconstruction. However, dissection of the tendinous intersections of rectus abdominis is technically difficult. The tendinous intersection has significant vascularity within its fascial layers raising in importance of technique in elevation. If tendinous intersections are damaged during the elevation of the rectus muscle, circulation to TRAM flap can be endangered. The purpose of this study is to evaluate the number of tendinous intersections and to predict anatomical position of the tendinous intersections. Methods: We dissected 182 consecutive TRAM flaps and measured the distance between xiphoid process and each tendinous intersection and evaluated the statistic correlation among the distance, patient's height and position of umbilicus. Results: In this study, in 30.7% of patients, two tendinous intersections were observed in one rectus abdominis muscle, in 67.7% three tendinous intersections, and in 1.6% four tendinous intersections, respectively. But there was no correlation between patient's height and the distance between xiphoid process and each tendinous intersection. Conclusion: It still remains difficult to predict the position of tendinous intersections just by topography before the dissection. Careful and meticulous dissection of the tendinous intersections is still required.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.10 no.2
• /
• pp.69-75
• /
• 1985

The proposed seal identification procedure consists of the smoothing, rotation, thinning, and matching techniques. The seal images which are scanned by CCTV are thresholded into the binary prctures of $256{\times}256$ pixels through A/D converter and 6502 microcomputer. After the sample and target images are ratated into an identical orientation, a thinning process is used to extract the skeletons of the character strobes. The wighted map is constructed by distance weight from which the distance weighted correlation C is computed. The C is compared with the dicision constant C or C for the purpose of seal indentification. The identification rate is 95% and the total CPU time is less than 3 minutes for each identification in the experiment.